1. Field of the Invention
The present invention relates to a pattern-forming method, and a radiation-sensitive composition.
2. Discussion of the Background
Chemically amplified type radiation-sensitive compositions for use in microfabrication by lithography generate an acid upon irradiation with a visible light, ultraviolet rays, etc., at light-exposed sites, and a chemical reaction that proceeds with the acid that serves as a catalyst allows the difference in dissolution rates in developer solutions to be produced between the light-exposed sites and light-unexposed sites, thereby enabling resist patterns to be formed on the substrate.
On the other hand, in a known technique for improving resolving power using characteristic features of such radiation-sensitive compositions without increasing the number of steps using a preexisting apparatus, an organic solvent having lower polarity than that of aqueous alkali solutions is used as a developer solution (see Japanese Unexamined Patent Application, Publication No. 2000-199953). This technique utilizes a possible increase of an optical contrast in the case in which an organic solvent is used, whereby formation of a fine pattern is enabled, contrary to the case in which an aqueous alkali solution is used as a developer solution for forming a trench pattern or hole pattern, accompanied by a poor optical contrast leading to a difficulty in formation of a fine pattern.